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中药苍耳草中苍耳亭的研究进展

江西化工 2024年第2期40卷 1-4页

作者：蔡鹏盛天露易永刘华陈冠宜刘永林王丽阳江西省检验检测认证总院检测认证技术发展研究院江西南昌330052 江西中医药大学药学院江西南昌330004 南昌医学院江西南昌330004

苍耳亭是一种天然倍半萜内酯类化合物,其主要来源为菊科植物苍耳草,具有十分丰富的生物活性,主要表现在抗肿瘤、抗菌、抗炎、抗病毒及抗虫等方面。苍耳亭的抗肿瘤效果较为显著,其作用机制主要与抑制血管生成有关。苍耳亭的抗菌作用在细... 详细信息

苍耳亭是一种天然倍半萜内酯类化合物,其主要来源为菊科植物苍耳草,具有十分丰富的生物活性,主要表现在抗肿瘤、抗菌、抗炎、抗病毒及抗虫等方面。苍耳亭的抗肿瘤效果较为显著,其作用机制主要与抑制血管生成有关。苍耳亭的抗菌作用在细菌和真菌方面均效果明显。此外,有研究发现苍耳亭在治疗过敏性皮炎、溃疡性结肠炎及杀虫方面亦具有良好的效果。本文从苍耳亭的来源及化学结构等角度出发对苍耳亭的药理作用、化学结构修饰以及全合成研究现状进行总结归纳,并对苍耳亭的应用前景及研究方向进行探讨,以期为苍耳亭的进一步开发提供参考。

关键词：苍耳草苍耳亭研究进展

Efficient production of ethyl levulinate from cassava over Al2(SO4)3 catalyst in ethanol–water system

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Journal of Energy Chemistry 2017年第1期26卷 115-120页

作者： Jin Tan Qiying Liu Lungang chen Tiejun Wang Longlong Ma guanyi chen School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Renewable Energy Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640GuangdongChina Guangdong Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640GuangdongChina

One-pot achievement of ethyl levulinate from cassava was conducted in ethanol–water system over several simple sulfate salt catalysts. Al2(SO4)3catalyst had the best performance in synthesizing ethyl levulinate comparing with those of a series of sulfate salts. The highest yields of ethyl levulinate was up to 39.27% as well as 7.78% levulinate acid when cassava was catalyzed in ethanol medium by adding 10 wt% water.13C and1H NMR spectroscopic investigations confirmed that isomerization of glucose to fructose over Al2(SO4)3catalyst is an important step in producing ethyl levulinate and levulinate acid. Due to aggregations of Al3+under hydrothermal conditions, tiny amount of Al3+were detected in filtrate at the percentage of 0.32% even if in absolute water. Brønsted and Lewis acids could improve the yield of ethyl levulinate and levulinate acid by synergistic effect. All results suggested that Al2(SO4)3was a simple and efficient catalyst for ethyl levulinate and levulinate acid production. © 2016 Science Press

关键词： Catalysts Ethanol Plants (botany) Sulfur compounds Waterworks

Spillover effect of environmental investment： evidence from panel data at provincial level in China

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Frontiers of Environmental Science & Engineering 2012年第3期6卷 412-420页

作者： Qunhui LIN guanyi chen Wencui DU Haipeng NIU School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China School of Economics&Business Administration Beijing Normal UniversityBeijing 100875China School of Business Renmin University of ChinaBeijing 100872China

This paper considers pollution density as a function of environmental investment. The higher envir- onmental investment, the lower pollution density. The lower the pollution density is the higher production technology becomes. This is called the spillover effect. We collected China＇s panel data at the provincial level from 2005 to 2009, and tested the spillover effect of environmental investment. This paper finds that the environmental investment influenced production technology positively. There is a significant positive relation between government expenditure and spillover effect.

关键词： environmental investment spillover effect endogenous growth

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常见塑料的热解特性及其动力学分析

环境工程 2024年第1期42卷 110-118页

作者：吕雯馨栾鹏鹏周慧王静兰何思蓉程占军李宁颜蓓蓓陈冠益天津大学环境科学与工程学院天津300350 天津市生物质废物利用重点实验室/天津市有机固废安全处置与能源利用重点实验室/中低温热能高效利用教育部重点实验室天津300072 江苏大学能源与动力工程学院江苏镇江212013 天津商业大学机械工程学院天津300134

研究塑料废弃物的热解特性有助于实现其清洁高效转化利用。借助热重技术总结对比了高密度聚乙烯、低密度聚乙烯和聚丙烯的不同升温速率(10,20,30,40,50℃/min)热解及不同催化剂(HZSM-5、Hβ和HUSY)催化热解的特性及规律。升温速率的增... 详细信息

研究塑料废弃物的热解特性有助于实现其清洁高效转化利用。借助热重技术总结对比了高密度聚乙烯、低密度聚乙烯和聚丙烯的不同升温速率(10,20,30,40,50℃/min)热解及不同催化剂(HZSM-5、Hβ和HUSY)催化热解的特性及规律。升温速率的增长使反应出现热迟滞现象,催化剂的加入对样品热解速率提高的效果也不尽相同。为了提供更有力的理论支持,运用3种动力学分析方法Coats-Redfern(CR)、Flynn-Wall-Ozawa(FWO)和分布式活化能法(DAEM),对样品在不同条件下的动力学参数进行计算和分析。CR模型验证了各热解反应符合一级化学反应模型并发现催化剂可以大幅降低反应活化能;FWO法和DAEM得到的表观活化能数值接近。DAEM模型显示活化能在转化率α增长的过程中先上升再逐步下降,在α=40%~50%时活化能最高,且包含动力学补偿效应。

关键词：塑料热解催化动力学分析

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Review of ionospheric irregularities and ionospheric electrodynamic coupling in the middle latitude region

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Earth and Planetary Physics 2021年第5期5卷 462-482页

作者： Yi Liu chen Zhou Tong Xu Qiong Tang ZhongXin Deng guanyi chen ZhuangKai Wang Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China

This paper briefly reviews ionospheric irregularities that occur in the E and F regions at mid-latitudes. Sporadic E(ES) is a common ionospheric irregularity phenomenon that is first noticed in the E layer. ES mainly appears during daytime in summer hemispheres, and is formed primarily from neutral wind shear in the mesosphere and lower thermosphere(MLT) region. Field-aligned irregularity(FAI) in the E region is also observed by Very High Frequency(VHF) radar in mid-latitude regions. FAI frequently occurs after sunset in summer hemispheres, and spectrum features of E region FAI echoes suggest that type-2 irregularity is dominant in the nighttime ionosphere. A close relationship between ES and E region FAI implies that ES may be a possible source of E region FAI in the nighttime ionosphere. Strong neutral wind shear, steep ES plasma density gradient, and a polarized electric field are the significant factors affecting the formation of E region FAI. At mid-latitudes, joint observational experiments including ionosonde, VHF radar, Global Positioning System(GPS) stations, and all-sky optical images have revealed strong connections across different scales of ionospheric irregularities in the nighttime F region, such as spread F(SF), medium-scale traveling ionospheric disturbances(MSTID), and F region *** suggest that different scales of ionospheric irregularities are generally attributed to the Perkins instability and subsequently excited gradient drift instability. Nighttime MSTID can further evolve into small-scale structures through a nonlinear cascade process when a steep plasma density gradient exists at the bottom of the F region. In addition, the effect of ionospheric electrodynamic coupling processes, including ionospheric E-F coupling and inter-hemispheric coupling on the generation of ionospheric irregularities, becomes more prominent due to the significant dip angle and equipotentiality of magnetic field lines in the mid-latitude ionosphere. Polar

关键词： ionospheric irregularity plasma instability neutral wind polarized electric field ionospheric electrodynamic coupling

Flame Structure of Methane and Kerosene Combustion with a Compact Concave Flame-Holder using the LES-pdf Method

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Journal of Thermal Science 2024年第1期33卷 222-234页

作者： WANG Fang WANG Yunfan WEI guanyi LIU Denghuan JIN Jie JONES P.William School of Energy and Power Engineering Beihang UniversityBeijingBeijing 100191China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Compact flame-holders for afterburners are an increasing requirement for modern aero ***,flame-holder design is non-trivial since high inlet temperatures,velocities,and elaborate structures induce complex turbulence,combustion,and spray coupling in modern *** this work,the LES-pdf and stochastic fields-Lagrangian particle spray methods are used to investigate methane and aviation kerosene combustion structures formed by new-type concave *** flow pattern,combustion mode,and flame structure of gaseous and liquid fuel around a concave flame-holder are analyzed,discussed,and compared with experimental *** reveal that the flame stability of a concave flame-holder is better than that of the non-concave ***,when using liquid fuel,the concave flame-holder forms a stable and compact *** results suggest concave flame-holders are a promising design for compact afterburners.

关键词： concave structure flame-holder LES-pdf spray combustion flame structure AECSC

酒糟厌氧发酵-气化耦合制备燃气环境影响评价

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环境工程 2024年第1期42卷 63-71页

作者：张笑颜王智李志宇李健颜蓓蓓左晓宇杨改秀陶俊宇陈冠益天津大学环境科学与工程学院天津300072 北京化工大学环境科学与工程系北京100029 中国科学院广州能源所中国科学院可再生能源重点实验室广东省新能源和可再生能源研究开发与应用重点实验室广州510640 天津商业大学机械工程学院天津300134

厌氧发酵-气化耦合技术是一种高效的生物质燃气化技术,具备显著的能源转化优势。为准确评估厌氧发酵程度对该耦合系统环境效益的影响,利用全生命周期分析方法,通过Gabi软件对所建立的不同厌氧发酵时间下酒糟厌氧发酵-气化耦合制备燃气... 详细信息

厌氧发酵-气化耦合技术是一种高效的生物质燃气化技术,具备显著的能源转化优势。为准确评估厌氧发酵程度对该耦合系统环境效益的影响,利用全生命周期分析方法,通过Gabi软件对所建立的不同厌氧发酵时间下酒糟厌氧发酵-气化耦合制备燃气模型进行环境影响评价。结果表明:厌氧发酵-气化梯度耦合反应系统基于能量流产生的环境正面影响可抵消基于物质流产生的环境负面影响,从而使系统获得正面的综合环境效益。厌氧发酵时间为8 d时系统环境影响结果最优,其环境影响潜值为-2.02×10^(-9)。对厌氧发酵-气化耦合系统的耦合程度进行控制,可在优化系统能量收益的同时产生最有利的环境影响,从而为耦合技术的应用提供理论指导。

关键词：酒糟厌氧发酵-气化耦合生命周期评价环境影响

Interpretable machine learning assisted spectroscopy for fast characterization of biomass and waste

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Interpretable machine learning assisted spectroscopy for fas...

Prediction of high-density polyethylene pyrolysis using kinetic parameters based on thermogravimetric and artificial neural networks

2023年有机固废处理与资源化利用大会

作者： Liang Rui chen Chao Tao Junyu Yan Beibei chen guanyi School of Environmental Science and Engineering Tianjin University School of Mechanical Engineering Tianjin University of Commerce Tianjin Key Lab of Biomass Wastes Utilization/Tianjin Engineering Research Center of Bio Gas/Oil Technology School of Science Tibet University

Background,Aims and *** characterization of biomass and waste(BW) is important to its downstream treatment and *** order to overcome the long duration and complex procedure problems of traditional BW characterization methods,the spectroscopy and machine learning based BW fast characterization method has been developed recently,and presented satisfactory ***,this fast characterization process is lack of interpretability towards its chemical insights,leading to less satisfactory recognition for its reliability and difficulty in expanding the further ***,this study proposed a hypothesis to the inner working mechanism of the spectroscopy and machine learning based BW fast characterization method:Infrared spectra have close qualitative and quantitative correlation with the functional groups' species and *** functional group has its specific element composition and heating value ***,the element composition and heating value results are obtained by processing the functional group information behind the infrared *** paper aimed to verify the hypothesis.A novel dimensionality reduction method with physicochemical meanings was proposed to explain the chemical insights of the machine learning *** high loading spectral peaks of BW,which contain the important information of the functional groups of raw materials,were selected as the results of dimensionality ***,combined with functional groups attribution of these spectral peaks,the machine learning model could provide clearer logic explanation of the input spectra and output characteristics,furthermore,provide support to the above *** paper discussed the results of the dimensionality reduction,evaluated the characterization performance between the newly dimensionality reduction method and PCA,moreover,explored the theoretical fundamentals of the input spectra on the output *** is hoped to provide

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Frontiers of Environmental Science & Engineering 2023年第1期17卷 63-74页

作者： Xiaoxiao Yin Junyu Tao guanyi chen Xilei Yao Pengpeng Luan Zhanjun cheng Ning Li Zhongyue Zhou Beibei Yan School of Mechanical Engineering Tianjin University of CommerceTianjin 300134China School of Environmental Science and Engineering Tianjin UniversityTianjin 300350China Key Laboratory for Power Machinery and Engineering of Ministry of Education Shanghai Jiao Tong UniversityShanghai 200240China

Pyrolysis is considered an attractive option and a promising way to dispose waste *** thermogravimetric experiments of high-density polyethylene(HDPE)were conducted from 105℃ to 900℃ at different heating rates(10℃/min,20℃/min,and 30℃/min)to investigate their thermal pyrolysis *** investigated four methods including three model-free methods and one modelfitting method to estimate dynamic ***,an artificial neural network model was developed by providing the heating rates and temperatures to predict the weight loss(wt.%)of HDPE,and optimized via assessing mean squared error and determination coefficient on the test *** optimal MSE(2.6297×10^(−2))and R^(2) value(R^(2)>0.999)were *** energy and preexponential factor obtained from four different models achieves the acceptable value between experimental and predicted *** relative error of the model increased from 2.4%to 6.8%when the sampling frequency changed from 50 s to 60 s,but showed no significant difference when the sampling frequency was below 50 *** result provides a promising approach to simplify the further modelling work and to reduce the required data storage *** study revealed the possibility of simulating the HDPE pyrolysis process via machine learning with no significant accuracy loss of the kinetic *** is hoped that this work could potentially benefit to the development of pyrolysis process modelling of HDPE and the other plastics.

关键词： HDPE Pyrolysis Kinetics Thermogravimetric ANOVA Artificial neural network